Employee Benefit Plans

6 Months Ended

Jun. 30, 2019

Compensation And Retirement Disclosure [Abstract]

Employee Benefit Plans

8. Employee Benefit Plans

The components of net periodic cost for our defined benefit pension plan and for our postretirement benefit plan are included in the following tables:

	Three Months Ended June 30,						Six Months Ended June 30,
Net Periodic Pension Cost	2019			2018			2019			2018
Interest cost	$	4.6		$	4.1		$	9.1		$	8.2
Actuarial loss amortization		3.2			3.6			6.4			7.2
Less: Expected return on plan assets		(5.9	)		(6.5	)		(11.8	)		(13.0	)
Net periodic pension cost	$	1.9		$	1.2		$	3.7		$	2.4

	Three Months Ended June 30,						Six Months Ended June 30,
Net Periodic Postretirement Benefit	2019			2018			2019			2018
Service benefit	$	—		$	—		$	—		$	—
Interest cost		0.1			0.1			0.2			0.2
Actuarial gain amortization		(0.6	)		(0.6	)		(1.2	)		(1.2	)
Prior service credit amortization		(0.1	)		(0.1	)		(0.1	)		(0.2	)
Net periodic postretirement benefit gain	$	(0.6	)	$	(0.6	)	$	(1.1	)	$	(1.2	)